private void OnMouseMove(object sender, MouseEventArgs e)
{
var dxScene = MainDXViewportView.DXScene;
if (dxScene == null)
{
return;
}
var mousePosition = e.GetPosition(ViewportBorder);
int xPos = (int)mousePosition.X;
int yPos = (int)mousePosition.Y;
if (xPos == _lastMousePosition.X && yPos == _lastMousePosition.Y)
{
return;
}
_lastMousePosition = new SharpDX.Point(xPos, yPos);
var mouseRay = dxScene.GetRayFromCamera(xPos, yPos);
// Using OctTree significantly improve hit testing performance
// Check this with uncommenting the following line (and commenting the use of OctTree):
//var hitResult = dxScene.GetClosestHitObject(mouseRay);
var hitResult = _octTree.HitTest(ref mouseRay, new DXHitTestContext(dxScene));
int selectedSphereIndex;
if (hitResult == null)
{
selectedSphereIndex = -1;
}
else
{
selectedSphereIndex = (hitResult.TriangleIndex * 3) / _oneMeshTriangleIndicesCount;
}
if (selectedSphereIndex == _lastSelectedSphereIndex)
{
return;
}
SelectSphere(selectedSphereIndex);
}